Enterovirus71 (EV71) utilise host microRNAs to mediate host immune system enhancing survival during infection.

Hand, Foot and Mouth Disease (HFMD) is a self-limiting viral disease that mainly affects infants and children. In contrast with other HFMD causing enteroviruses, Enterovirus71 (EV71) has commonly been associated with severe clinical manifestation leading to death. Currently, due to a lack in understanding of EV71 pathogenesis, there is no antiviral therapeutics for the treatment of HFMD patients. Therefore the need to better understand the mechanism of EV71 pathogenesis is warranted. We have previously reported a human colorectal adenocarcinoma cell line (HT29) based model to study the pathogenesis of EV71. Using this system, we showed that knockdown of DGCR8, an essential cofactor for microRNAs biogenesis resulted in a reduction of EV71 replication. We also demonstrated that there are miRNAs changes during EV71 pathogenesis and EV71 utilise host miRNAs to attenuate antiviral pathways during infection. Together, data from this study provide critical information on the role of miRNAs during EV71 infection.

Elucidating the host-pathogen interaction between human colorectal cells and invading Enterovirus 71 using transcriptomics profiling.

Enterovirus 71 (EV71) is one of the main etiological agents for Hand, Foot and Mouth Disease (HFMD) and has been shown to be associated with severe clinical manifestation. Currently, there is no antiviral therapeutic for the treatment of HFMD patients owing to a lack of understanding of EV71 pathogenesis. This study seeks to elucidate the transcriptomic changes that result from EV71 infection. Human whole genome microarray was employed to monitor changes in genomic profiles between infected and uninfected cells. The results reveal altered expression of human genes involved in critical pathways including the immune response and the stress response. Together, data from this study provide valuable insights into the host-pathogen interaction between human colorectal cells and EV71.

Characterisation of enterovirus 71 replication kinetics in human colorectal cell line, HT29.

Hand, Foot and Mouth Disease (HFMD), a contagious viral disease that commonly affects infants and children with blisters and flu like symptoms, is caused by a group of enteroviruses such as Enterovirus 71 (EV71) and coxsackievirus A16 (CA16). However some HFMD caused by EV71 may further develop into severe neurological complications such as encephalitis and meningitis. The route of transmission was postulated that the virus transmit from one person to another through direct contact of vesicular fluid or droplet from the infected or via faecal-oral route. To this end, this study utilised a human colorectal adenocarcinoma cell line (HT29) with epithelioid morphology as an in vitro model for the investigation of EV71 replication kinetics. Using qPCR, viral RNA was first detected in HT29 cells as early as 12 h post infection (hpi) while viral protein was first detected at 48 hpi. A significant change in HT29 cells' morphology was also observed after 48 hpi. Furthermore HT29 cell viability also significantly decreased at 72 hpi. Together, data from this study demonstrated that co-culture of HT29 with EV71 is a useful in vitro model to study the pathogenesis of EV71.

A multi-subunit chlamydial vaccine induces antibody and cell-mediated immunity in immunized koalas (Phascolarctos cinereus): comparison of three different adjuvants.

PROBLEM: Chlamydial infections represent a major threat to the survival of the koala. Infections caused by Chlamydia pecorum cause blindness, infertility, pneumonia and urinary tract infections and represent a threat to the survival of the species. Little is known about the immune response in koalas, or the safety of commonly used adjuvants for induction of protective systemic and mucosal immunity. METHOD: of study In the present study, we immunized 18 healthy female koalas subcutaneously with a combination of three chlamydial antigens [major outer membrane protein (MOMP), NrdB and TC0512 (Omp85)] mixed with one of three different adjuvants [Alhydrogel, Immunostimulating Complex (ISC) and TiterMax Gold]. RESULTS: All adjuvants induced strong neutralizing IgG responses in plasma against the three antigens with prolonged responses lasting more than 270 days seen in Alhydrogel and ISC immunized animals. Cloacal IgG responses lasting >270 days were also induced in ISC-immunized animals. Chlamydia-specific peripheral blood mononuclear cell proliferative responses were elicited by both Alhydrogel and ISC, and these lasted >270 days in the ISC group. CONCLUSION: The data show that a multi-subunit chlamydial vaccine, given subcutaneously, can elicit Chlamydia-specific cell-mediated and antibody responses in the koala demonstrating that the development of a protective vaccine is feasible.